HR 5171

V766 Centauri
Location of HR 5171 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
A
Right ascension 13h 47m 10.864s[1]
Declination −62° 35′ 22.95″[1]
Apparent magnitude (V) 6.1 - 7.5[2]
B
Right ascension 13h 47m 09.953s[3]
Declination −62° 35′ 15.99″[4]
Apparent magnitude (V) 9.83[4]
Characteristics
A
Spectral type K0 0-Ia[5]
B−V color index +2.499[4]
Variable type EB + SDOR?[6]
B
Spectral type B0 Ibp[7]
B−V color index +0.39[4]
Astrometry
Radial velocity (Rv)−38.20[8] km/s
Distance4,900 – 12,700 ly
(1,500[9] – 3,900[10] pc)
A
Proper motion (μ) RA: −5.648[1] mas/yr
Dec.: −1.797[1] mas/yr
Parallax (π)0.2459 ± 0.0514 mas[1]
Distanceapprox. 13,000 ly
(approx. 4,100 pc)
Absolute magnitude (MV)−9.2[11]
B
Proper motion (μ) RA: −5.715[3] mas/yr
Dec.: −2.143[3] mas/yr
Parallax (π)0.3257 ± 0.0126 mas[3]
Distance10,000 ± 400 ly
(3,100 ± 100 pc)
Absolute magnitude (MV)−5.8[12]
Orbit[2]
PrimaryAa
CompanionAb
Period (P)1,304±6 days
Semi-major axis (a)2,028 - 2,195 R☉
Eccentricity (e)0
Inclination (i)>60°
Details
Aa
Mass27 – 36[13][14] M☉
Radius1,060 – 1,160,[9] 1,315[2] – 1,575[14] R☉
Luminosity200,000 – 251,000,[9] 630,000+60,000
−55,000[13] L☉
Surface gravity (log g)−0.5±0.6[13] cgs
Temperature4,470 – 5,012[9] K
Age3.5[10] Myr
Ab
Mass5+15
−3[14] M☉
Radius312 - 401,[2] 650±150[14] R☉
Temperature4,800 - 5,200[2] K
B
Radius20 R☉
Luminosity160,000[15] L☉
Surface gravity (log g)3.0 - 3.5[7] cgs
Temperature26,000[7] K
Age4[10] Myr
Other designations
V766 Cen, HR 5171, HD 119796, HIP 67261, SAO 252448, CD−61°3988, WDS J13472-6235, AAVSO 1340-62
Database references
SIMBADdata

HR 5171, also known as V766 Centauri, is a yellow hypergiant in the constellation Centaurus. It is said to be either an extreme red supergiant (RSG) or recent post-red supergiant (Post-RSG) yellow hypergiant (YHG), both of which suggest it is one of the largest known stars. The star's diameter is uncertain but likely to be between 1,100 and 1,600 times that of the Sun. It is 3.6 kpc (11,700 light years) from Earth.

A 2014 publication hypothesized the star to be a contact binary, sharing a common envelope of material with a smaller yellow supergiant and secondary star, the two orbiting each other every 1,304 ± 6 days. A recent publication (2019) rules out this hypothesis, and the distance of HR 5171 has been revised to 5,200 ± 1,600 light years and its radius to 3-5 AU (i.e. 650 to 1080 times that of the Sun).[9]

An optical companion, HR 5171B, may or may not be at the same distance as the yellow supergiant.[9]

  1. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c d e Chesneau, O.; Meilland, A.; Chapellier, E.; Millour, F.; Van Genderen, A. M.; Nazé, Y.; Smith, N.; Spang, A.; Smoker, J. V.; Dessart, L.; Kanaan, S.; Bendjoya, Ph.; Feast, M. W.; Groh, J. H.; Lobel, A.; Nardetto, N.; Otero, S.; Oudmaijer, R. D.; Tekola, A. G.; Whitelock, P. A.; Arcos, C.; Curé, M.; Vanzi, L. (2014). "The yellow hypergiant HR 5171 A: Resolving a massive interacting binary in the common envelope phase". Astronomy & Astrophysics. 563: A71. arXiv:1401.2628v2. Bibcode:2014A&A...563A..71C. doi:10.1051/0004-6361/201322421. S2CID 52108686.
  3. ^ a b c d Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  4. ^ a b c d Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27. Bibcode:2000A&A...355L..27H. doi:10.1888/0333750888/2862. ISBN 0333750888.
  5. ^ Keenan, P. C.; McNeil, R. C. (1989). "The Perkins catalog of revised MK types for the cooler stars". The Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373.
  6. ^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  7. ^ a b c Van Genderen, A. M.; Nieuwenhuijzen, H.; Lobel, A. (2015). "An early detection of blue luminescence by neutral PAHs in the direction of the yellow hypergiant HR 5171A?". Astronomy & Astrophysics. 583: A98. arXiv:1509.07421. Bibcode:2015A&A...583A..98V. doi:10.1051/0004-6361/201526392. S2CID 56270146.
  8. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  9. ^ a b c d e f van Genderen, A. M.; Lobel, A.; Nieuwenhuijzen, H.; Henry, G. W.; De Jager, C.; Blown, E.; Di Scala, G.; Van Ballegoij, E. J. (2019). "Pulsations, eruptions, and evolution of four yellow hypergiants". Astronomy and Astrophysics. 631: A48. arXiv:1910.02460. Bibcode:2019A&A...631A..48V. doi:10.1051/0004-6361/201834358. S2CID 203836020.
  10. ^ a b c Karr, J. L.; Manoj, P.; Ohashi, N. (2009). "Gum 48d: An Evolved H II Region with Ongoing Star Formation". The Astrophysical Journal. 697 (1): 133–147. arXiv:0903.0934. Bibcode:2009ApJ...697..133K. doi:10.1088/0004-637X/697/1/133. S2CID 17962808.
  11. ^ Humphreys, R. M. (1978). "Studies of luminous stars in nearby galaxies. I. Supergiants and O stars in the Milky Way". Astrophysical Journal. 38: 309. Bibcode:1978ApJS...38..309H. doi:10.1086/190559.
  12. ^ Humphreys, R. M.; Strecker, D. W.; Ney, E. P. (1971). "High-luminosity G supergiants". Astrophysical Journal. 167: L35. Bibcode:1971ApJ...167L..35H. doi:10.1086/180755.
  13. ^ a b c Wittkowski, M.; Arroyo-Torres, B.; Marcaide, J. M.; Abellan, F. J.; Chiavassa, A.; Guirado, J. C. (2017). "VLTI/AMBER spectro-interferometry of the late-type supergiants V766 Cen (=HR 5171 A), σ Oph, BM Sco, and HD 206859". Astronomy & Astrophysics. 597: A9. arXiv:1610.01927. Bibcode:2017A&A...597A...9W. doi:10.1051/0004-6361/201629349. S2CID 55679854.
  14. ^ a b c d Wittkowski, M; Abellan, F. J; Arroyo-Torres, B; Chiavassa, A; Guirado, J. C; Marcaide, J. M; Alberdi, A; De Wit, W. J; Hofmann, K.-H; Meilland, A; Millour, F; Mohamed, S; Sanchez-Bermudez, J (28 September 2017). "Multi-epoch VLTI-PIONIER imaging of the supergiant V766 Cen: Image of the close companion in front of the primary". Astronomy & Astrophysics. 1709: L1. arXiv:1709.09430. Bibcode:2017A&A...606L...1W. doi:10.1051/0004-6361/201731569. S2CID 54740936.
  15. ^ Jim Kaler. "V766 Centauri". Retrieved 2015-11-21.